A novel model to manage air cargo disruptions caused by global catastrophes such as Covid-19

The outbreak of the COVID-19 pandemic has drastically disrupted the air cargo industry. This disruption has taken many directions, one of which is the demand imbalance which occurs due to the sudden change in the cargo capacity, as well as demand. Therefore, the random change leads to excessive demand in some routes (hot-selling routes), while some other routes suffer from a big shortage of demand (underutilized routes). Routes are substitutable when there are several adjacent airports in the Origin & Destination (O&D) market. In this market, demand imbalance between substitutable routes occurs because of the above reasons. To tackle the demand imbalance problem, a novel model is introduced to estimate the quantity combinations which maintains the balance between underutilized and hot-selling routes. This model is a variant of the classic Cournot model which captures different quantity scenarios in the form of the best response for each route compared to the other. We then cultivate the model by integrating the Puppet Cournot game with the quantity discount policy. The quantity discount policy is an incentive which motivates the freight forwarders to increase their orders in the underutilized routes. After conducting numerical experiments, the results reveal that the profit can increase up to 25% by using the quantity discount. However, the quantity discount model is only applicable when the profit increase in the hot-selling route is greater than the profit decrease in the underutilized route.     

区域经济发展不平衡与土地违法：基于地方政府经济增长激励的视角

研究目的:探究地方政府经济增长激励背景下,区域经济发展不平衡对土地违法行为的影响。研究方法:基于经济和社会科学领域有关发展不平衡及其影响效应的理论观点,结合中国特定的地方政府经济增长激励机制,以及土地利用与管理实际,探讨区域经济发展不平衡对土地违法行为的影响机理,并通过构建计量经济模型进行相应的实证检验。研究结果:区域内部经济发展差异的扩大确实会导致更多土地违法案件的产生和违法用地规模的增加;另外,在不同经济发展地区,区域内部经济发展差异变化对土地违法的具体影响有所不同。发达地区内部经济发展差异的扩大对土地违法的影响主要表现在违法面积上,而欠发达地区内部经济发展差异的扩大对土地违法的影响则主要表现在违法案件数上。研究结论:区域经济发展不平衡是导致土地违法行为的重要因素之一,促进和实现地区间的均衡发展有助于减少土地违法现象。     

Exploring the nexus between bank market power and exports

Although the literature underlines the importance of finance in international trade, no prior study has examined the causal links between market power in banking and export performance. Using a world sample over the 1997-2010 period, and accounting for both observed and unobserved country heterogeneity, we find a positive effect of bank market power on exports, especially in high-income countries. We also document that this export-enhancing effect is more potent in informationally opaque markets. Our findings accord with information hypothesis which suggests that market power in banking induces stronger bank-firm relationships which can generate benefits for both borrowers and lenders. Policy interventions should, therefore, promote the supply of relationship lending as a means to mitigate informational asymmetries in the export market.     

Worktime control and work stress: the moderating effect of self-comparisons and social comparisons

Abstract

Perceived work-related stress has increased notably in recent years, reducing individuals’ well-being and increasing organizations’ and economies’ costs. This study focuses on worktime control as a key approach to reducing work stress, as the extant research on its effects reports inconsistent results. The study argues that comparisons play a major role in how work stress, conceptualized as effort-reward imbalance, occurs. Ordinary least squares is used to test hypotheses with a sample of 1721 employees from Germany to determine whether employees’ prior worktime control and employees’ referents’ worktime control affect the relationship between worktime control and work stress. Results show that (1) worktime control is negatively associated with the experience of work stress, (2) employees’ prior worktime control moderates the relationship between worktime control and work stress, and (3) there is no moderating effect of employees’ referents’ worktime control. The results are discussed in light of gift-exchange theory and related empirical findings.     

中央与地方纵向财政不平衡的实证研究:1978-2003

本文对纵向财政不平衡的传统理论与新近发展进行了回顾,根据纵向财政不平衡的传统定义,对1978-2003年我国中央与地方纵向财政进行了实证分析,我们发现1978-1984年纵向财政处于正向不平衡状态,1985-1993年纵向财政基本平衡,1994-2003年纵向财政处于反向不平衡状态。分税制后中央本级财政收支正缺口呈扩大趋势,而地方负的财政缺口也呈扩大趋势,而且中央财政的正缺口并不足以弥补地方财政的负缺口,在地方举债受到严格限制的条件下,为弥补缺口,地方政府扩大预算外收入是其唯一途径。     

金融结构理论对我国金融结构调整优化的启示

R.W.戈德史密斯的金融结构理论是西方金融理论中的重要流派。该理论分析了决定金融发展的因素、金融结构与金融发展对经济增长的引致效应以及各国金融发展中的普遍规律性趋势。戈德史密斯认为,金融发展的实质就是金融结构的变化,金融相关比率是衡量金融结构演变程度最重要的数量指标;世界上存在一条主要的金融发展道路,在这条道路上,金融结构的变化呈现出一定的规律性。金融结构理论的研究方法和基本框架对我国金融结构调整和结构优化具有重要启示。     

Modeling Methods for Discrete Choice Analysis

This paper introduces new forms, sampling and estimation approaches fordiscrete choice models. The new models include behavioral specifications oflatent class choice models, multinomial probit, hybrid logit, andnon-parametric methods. Recent contributions also include new specializedchoice based sample designs that permit greater efficiency in datacollection. Finally, the paper describes recent developments in the use ofsimulation methods for model estimation. These developments are designed toallow the applications of discrete choice models to a wider variety ofdiscrete choice problems.     

Fundamentals and Exchange Rate Prediction Revisited

This paper measures latent fundamental exchange rates with independent component‐based rates constructed from a cross‐section of exchange rates and then uses their deviations from exchange rates to forecast. Empirical results indicate that the independent component‐based model and its Taylor rule and purchasing power parity augmented models are superior to the random walk in predicting exchange rates. These results are robust to several scenarios and are likely to be observed if the U.S. sources and the recursive scheme are applied. Our results reveal that information regarding the third moment of exchange rate changes is helpful to explain exchange rate movements.     

Nearly exact sample size calculation for powerful non‐randomized tests for differences between binomial proportions

In the case of two independent samples, it turns out that among the procedures taken in consideration, BOSCHLOO'S technique of raising the nominal level in the standard conditional test as far as admissible performs best in terms of power against almost all alternatives. The computational burden entailed in exact sample size calculation is comparatively modest for both the uniformly most powerful unbiased randomized and the conservative non‐randomized version of the exact Fisher‐type test. Computing these values yields a pair of bounds enclosing the exact sample size required for the Boschloo test, and it seems reasonable to replace the exact value with the middle of the corresponding interval. Comparisons between these mid‐N estimates and the fully exact sample sizes lead to the conclusion that the extra computational effort required for obtaining the latter is mostly dispensable. This holds also true in the case of paired binary data (McNemar setting). In the latter, the level‐corrected score test turns out to be almost as powerful as the randomized uniformly most powerful unbiased test and should be preferred to the McNemar–Boschloo test. The mid‐N rule provides a fairly tight upper bound to the exact sample size for the score test for paired proportions.     

The market microstructure of the European climate exchange

This paper analyzes the market microstructure of the European Climate Exchange, the largest EU ETS trading venue. The ECX captures 2/3 of the screen traded market in EUA and more than 90% in CER. Volume growth has averaged 277% in EUA between 2005 and 2009 and 724% in CER since 2007. Spreads range from €0.0188 to €0.0406 for EUA and €0.0276 to €0.0796 for CER. The median proportion of the spread due to adverse selection reaches 76% for EUA and 75% for CER. Realized volatility, bid-ask spreads and adverse selection costs decline with verified emission releases. Market impact estimates imply that an average trade will move the EUA market by 1.06 euro centimes and the CER market 1.45. The ECX is providing between 75% and 88% of price discovery for EUA trading and between 64% and 72% for CER. We find imbalances in the order book help predict returns for up to three days. A simple trading strategy that enters the market long or short when the order imbalance is strong is profitable even after accounting for spreads and market impact.